生化/生理作用
G-CSF is a proliferation, differentiation, survival, and activation factor for hematopoietic cells of the restricted neutrophilic granulocyte lineage. It is produced by macrophages activated by endotoxin (LPS), by monocytes activated by TNF-α with IFNγ, by fibroblasts and endothelial cells activated by IL-1 or TNF-α, and by bone marrow stromal cells activated by IL-1 or LPS. It is suggested that during the inflammatory process endotoxins stimulate tissue macrophages to produce not only G-CSF but several other cytokines, including IL-1 and TNF-α, which in turn stimulate more G-CSF release from endothelial cells and fibroblasts. G-CSF can also synergize with IL-3 to shorten the G0 period of early hematopoietic progenitors. In addition to the namesake proliferative activity, G-CSF acts on mature neutrophils to enhance their survival and to stimulate their tumorcidal activity. Human G-CSF binds and activates a 130 kD to150 kD glycoprotein single chain receptor that has been classified as a member of the hematopoietic (cytokine) receptor family, the cytokine receptor class I, or the gp130 related cytokine receptor family (although it does not apparently bind to gp130). G-CSF receptors can be found on neutrophils, myeloid leukemia cells that respond to G-CSF, bone marrow cells of neutrophilic granulocyte lineage, and on placental trophoblasts, plus a soluble form may be expressed. Two forms of human G-CSF (177 and 174 amino acids) are synthesized from a single gene by alternative splicing, but murine G-CSF is a single expressed form of 178 amino acids. Human and murine G-CSF share 73% amino acid sequence homology and full cross-reactivity.
Granulocyte colony-stimulating factor (G-CSF) is a lineage-restricted hematopoietic growth factor, stimulating final mitotic divisions and the terminal cellular maturation of the partially differentiated hematopoietic progenitors. G-CSF3,4 is produced by monocytes and fibroblasts. It stimulates granulocyte colony formation, activates neutrophils and mature granulocytes, and promotes differentiation of certain myeloid leukemic cells. Natural G-CSF is a glycoprotein of 177 amino acids and a molecular weight of 19 kDa.5 Human and murine G-CSF have about 75% homology and show biological cross-reactivity.
外形
Lyophilized from a 0.2 μm filtered solution in 10 mM citric acid, 0.01% TWEEN® 20, pH 4.0, containing 50 μg bovine serum albumin per 1 μg of cytokine.